Recent image forming apparatuses of an electrophotographic system feature high-speed performance, multi-functions, and network functions and are expanding their applications as printing apparatuses via connection with a large-capacity paper feed apparatus and a large-capacity stacker. When an image forming apparatus is used as a printing apparatus, only a single apparatus can carry out operations from printing to bookbinding by connecting a bookbinding apparatus thereto to bookbind printed matter.
As the above bookbinding apparatus, disclosed is a smaller-sized, glue applying bookbinding apparatus in which a sheet bundle storing section, a glue (adhesive) coating section, a coversheet feed section, and a coversheet folding section are tandemly arranged in the vertical direction (for example, refer to Patent Document 1).
The glue applying bookbinding apparatus disclosed in Patent Document 1 uniformly coats an adhesive, using an adhesive coating roller, on the spine portion of a sheet bundle stored and nipped in the sheet bundle storing section. The adhesive is coated only on the spine portion of the sheet bundle, whereby the adhesion area is small, resulting in inadequate strength in glue applying bookbinding. Therefore, when the thus-produced booklet is opened, some sheets may be dropped off due to peeling of adhered portions.
In contrast, in a bookbinding apparatus carrying out case bookbinding operations in which the spine portion of a sheet bundle is bonded with a coversheet, a bookbinding apparatus is disclosed in which in a sheet conveyance path of the bookbinding apparatus, a notch forming section is provided to form notches on the edge side coated with an adhesive during sheet bookbinding processing (for example, refer to Patent Document 2).